• Proceedings of the Safety Management and Science Conference
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• 2011.04a
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• pp.95-99
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• 2011

The research analyzes structure models of Repeated Measurement Design (RMD) and Hierarchical Design (HD). The experimental unit of RMD model is living organisms, such as human. In contrast, HD is used when all the factors are random. The HD models are derived from R:B:A, R:C:B:A and R:C:($A{\times}B$).

• International Journal of Aeronautical and Space Sciences
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• v.18 no.3
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• pp.414-424
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• 2017

This paper introduces an experimental device which can measure accurate aerodynamic forces without support interference in wide experimental region for wind tunnel test of micro aerial vehicles (MAVs). A stereo pattern recognition (SPR) method was introduced to a magnetic suspension and balance system (MSBS), which can eliminate support interference by levitating the experimental model, to establish wider experimental region; thereby MSBS-SPR integrated system was developed. The SPR method is non-contact, highly accurate three-dimensional position measurement method providing wide measurement range. To evaluate the system performance, a series of performance evaluations including SPR system measurement accuracy and 6 degrees of freedom (DOFs) position/attitude control of the MAV model were conducted. This newly developed system could control the MAV model rapidly and accurately within almost 60mm for translational DOFs and 40deg for rotational DOFs inside of $300{\times}300mm$ test section. In addition, a static wind tunnel test was conducted to verify the aerodynamic force measurement capability. It turned out that this system could accurately measure the aerodynamic forces in low Reynolds number, even for the weak forces which were hard to measure using typical balance system, without making any mechanical contact with the MAV model.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.3
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• pp.47-54
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• 2009

In the manufacturing industry, there has been a significant increase in the use of coordinate measuring machines(CMM). In this paper, the sources of CMM measurement performance are discussed. The effects of workpiece position, length and orientation are analyzed by using the design of experiments. Both a fractional factorial design and a factorial design are employed to conduct the experimental study. The analysis of variance is performed to determine the significance of factors in the experiment and regression analysis is applied to make the measurement approximate model. The results show that position along the Z axis, length and orientation affect the CMM measurement performance.

• Korean Journal of Child Studies
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• v.30 no.5
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• pp.225-243
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• 2009

This study analyzed the effects of dynamic assessment in terms of scaffolding group types and young children's measurement ability levels. Participants were five-year-old children in Busan divided into 2 experimental groups and control groups. The Assessment Tools for Young Children's Measurement Ability (Ko & Hwang, 2008) consisted of 4 sub tests for ‘length', 'width', and 'weight' concepts. Data were analyzed by t-test and ANOVA. Results showed significant differences between experimental and control groups in post-test scores, but no significant differences between individual and peer collaboration groups in amount of scaffolding. Significant improvements showed in all of the measurement ability level groups : individual higher, individual lower, peer collaboration higher and peer collaboration lower level scaffolding groups.

• Journal of Ocean Engineering and Technology
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• v.16 no.2
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• pp.60-66
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• 2002

The remote measurement system(RMS) as a new experimental method is limited in its application to crack measurement at elevated temperatures because of the oxide layer on the specimen surface. Since TiAIN and Cr coating layers have a high resistance to oxidation and wear, this paper proposed a TiAIN and Cr coating technique for specimens to facilitate the measurement of crack growth behavior using RMS. To investigate the effects of the coating layer, tension and fatigue tests were carried out at room temperature and at $538^{\circ}C$. The test material was 1Cr-1Mo-0.25V steel which is widely used as a turbine rotor material. From the experimental results, it was found that the mechanical properties of the TiAIN and Cr coated specimens were similar to those of the substrate. Accordingly, the TiAIN and Cr coated layer had hardly any influence on the fatigue crack propagation.

• 유체기계공업학회:학술대회논문집
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• 2003.12a
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• pp.107-114
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• 2003

The influence of property difference in refraction index on micro PIV measurement of two-fluid flow in a microchannel was analyzed. The difference of measurement planes in two fluids would bring misunderstanding of the physics. The objective-imaging system for two-fluid flow measurement was presented, and the condition for measurement of valid velocity profile across two-fluid interface was derived. A micro PIV experimental system was set up to measure two-fluid flow inside a Y-shape microchannel. Under the conditions, three cases of two-fluid flow of glycerol solutions at different concentration (${\phi}$), e.g., (${\phi}=0\;and\;{\phi}=0.2,\;{\phi}=0.1\;and\;{\phi}=0.5,\;{\phi}=0\;and\;{\phi}=0.6$, were measured. Close agreement of experimental and numerical results was found.

• The Mathematical Education
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• v.48 no.3
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• pp.329-352
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• 2009

The purpose of this study was to investigate the effects of small group cooperative communicative activities on the strategies for estimating measurement. To do this, two research questions were set as follow: First, are there any differences between strategies employed by students in the experimental group and the control group before and after the estimating measurement activities? Second, are there any differences between strategies employed by students in different ability levels(upper, middle, lower) of pre-estimating measurement test in the experimental group? The research results were drawn from the investigation as below: First, the strategical change of before and after the estimating measurement tasks in the experimental group was quite noticeable. Unlike the small strategical change in the control group, small group cooperative communicative learning resulted in a decrease of simple memorization and guessing strategies and an increase of refined strategies such as the standard strategy, clustering, unit load and so on. Second, mathematical communicative activities in a small group cooperative learning showed that the students in the upper level of pre-estimating measurement test used more refined strategies and the students in the lower level used simple memorization and guessing strategy more frequently. And through interaction in small group, students could have chances to recognize error of strategies and to modify and learn strategies. In conclusion, small group cooperative activities allowed students to have chances to communicate mathematically and it is a efficient way of helping students learn estimating measurement strategies.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.300-301
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• 2014

Measurement of beam deflection is a common procedure to determine proper behavior of the structure. Either LVDT (Linear Variable Displacement Transformer) or strain gauge is usually used in experiments. A newly developed coordinate reading measurement system can be also applied for the deflection measurements. In this study, an experimental measurement was made on a laboratory size beam specimen to examine the possibility of the use of such coordinate measurement system. Results have shown the possibility of utilizing the new system for beam deflection measurement.

• Journal of Korean Clinical Nursing Research
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• v.14 no.1
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• pp.33-44
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• 2008

Purpose: This study was performed to determine the effects of foot reflexology on pain and quality of sleep in patients with terminal cancer. Method: Quai-experimental research design was used. The subjects of this study were consisted of 19 for experimental group and 18 for control group. Visualue Scale(VAS) was used as the measurement tool of pain in this study, Verra & Snyder-Halpern Sleep Scale(VSH) and Visual Analogue Scale(VAS) were used as the measurement tool of perceived quality of sleep. Data were analyzed using statistical methods such as frequency, percent, $x^2$-test, t-test using SPSS WIN 12.0 program. Results: The hypothesis 1 that the experimental group with reflexology has less degree of pain than the control group without reflexology was supported (t=5.41, p<.001). The hypothesis 2 that the experimental group with reflexology has higher degree of VSH Scale than the control group without reflexology was supported(t=2.37, p=.02). The hypothesis 3 that the experimental group with reflexology has the difference among the mean of sleep VAS Scale during the 12 measurement periods was not supported(F=1.63, p=.08), and no significant interactions between group and time. Conclusion: It is considered that reflexology is effective for reducing cancer pain and improving quality of sleep in patients with terminal cancer.

• Nuclear Engineering and Technology
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• v.51 no.7
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• pp.1853-1859
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• 2019

The two-thermocouple method was investigated experimentally to evaluate its accuracy for the measurement of local wall temperature and heat flux on a heat transfer tube with an electric heater rod installed in an annulus channel. This work revealed that a thermocouple flush-mounted in a surface groove serves as a good reference method for the accurate measurement of the wall temperature, whereas two thermocouples installed at different depths in the tube wall yield large bias errors in the calculation of local heat flux and wall temperature. These errors result from conductive and convective changes due to the fin effect of the thermocouple sheath. To eliminate the bias errors, we proposed a calibration method based on both the local heat flux and Reynolds number of the cooling water. The calibration method was validated with the measurement of local heat flux and wall temperature against experimental data obtained for single-phase convection and two-phase condensation flows inside the tube. In the manuscript, Section 1 introduces the importance of local heat flux and wall temperature measurement, Section 2 explains the experimental setup, and Section 3 provides the measured data, causes of measurement errors, and the developed calibration method.